<template>
  <div class="subject">
    <span>{{ num1 }}</span>
    <span>+</span>
    <span>{{ num2 }}</span>
    <span>=</span>
    <input type="number" v-model.number="result" :disabled="isDis" />
    <button @click="submitFn" :disabled="isDis">提交</button>
  </div>
</template>

<script>
export default {
  data() {
    return {
      num1: Math.floor(Math.random() * (50 - 0 + 1) + 0),
      num2: Math.floor(Math.random() * (50 - 0 + 1) + 0),
      result: null,
      isDis: false, //禁用
    };
  },
  methods: {
    submitFn() {
      this.isDis = true;

      let resStr = this.num1 + this.num2 === this.result ? "正确" : "错误";
      this.$emit("res", resStr, this.index);
    },
  },
  props: ["index"],
};
</script>

<style scoped>
.subject {
  margin: 5px;
  padding: 5px;
  font-size: 20px;
}
.subject span {
  display: inline-block;
  text-align: center;
  width: 20px;
}
.subject input {
  width: 50px;
  height: 20px;
}
</style>